Computer crashes repeatedly in final 4 minutes of Apollo landingThe MIT team located the source of the error with only two or three hours to spare. In anticipation of a possible abort, Aldrin had insisted that the spacecraft’s rendezvous radar remain turned on. This system pointed upward, allowing it to track Collins in the command module. During the descent, the dial for the rendezvous radar had been turned to the wrong setting. Normally, this shouldn’t have caused a problem. But because of a design defect, every once in a while the system would bombard the computer with unnecessary requests. It was the worst kind of error: erratic, subtly dangerous, and difficult to reproduce.